The present invention refers to improvements introduced in the mouthpieces which are used to facilitate giving up the smoking habit.
More concretely, the invention refers to mouthpieces of the kind which comprise an external air inlet, adjustable between zero and a maximum, which permits mixing the smoke drawn in by the smoker with a variable proportion of fresh air, reducing the toxicity of the mixture, and permitting the metabolism of the smoker to habituate itself with minimum effort to progressively decreasing nicotine levels.
Still more concretely, the invention refers to mouthpieces of the type which comprise a diluting body provided with an axial bore through which circulates the smoke coming from the cigarette, and is provided with at least one opening communicating with the exterior, whose effective dimensions can be regulated by screwing to a greater or lesser degree a regulating body into the diluting body, so that the proportion of fresh air coming from the outside, which in each case is mixed with the smoke drawn in by the smoker, can be regulated with full precision and in a perfectly safe manner.
To conceal said inlet orifices for the outside air from sight, it is normal, in the mouthpieces of the type referred to, to provide a metal sleeve, which envelops the diluting body, and which forms at its end the pan or housing in which fits the end of the cigarette to be consumed. It is also normal that the sleeve piece is mounted so that it can shift between limits, in an axial direction, with respect to the axially pierced stem which fixes it to the end of the diluting body, constituting an ejecting device. The circulation of outside air toward the orifice or orifices provided in the diluting body occurs through the annular chamber defined by the clearance between it and the metal sleeve surrounding it. This arrangement greatly complicates the mounting, making it necessary to manufacture this assembly with exceptional precision, and moreover, brings about a rapid aging in the outward appearance of the mouthpiece, as the friction which inevitably occurs between the edge of the sleeve -- which is completely cantilever mounted -- and the surface of the diluting body containing the air inlet orifices, causes the scoring of this piece, which is normally made of anodized aluminum or having any other suitable finish.